BACKGROUND: Air pollution has been hypothesized as a potential risk factor for prostate cancer, while previous studies on the topic mainly focused on single pollutant and the results were inconsistent. This study aimed to investigate the association between long-term exposure to multiple air pollutants and the risk of prostate cancer and their joint effect. METHODS: This study included 210,722 men free of prostate cancer at baseline from the UK Biobank. Data on ambient air pollutants, including particulate matter with diameters ≤2.5 μm (PM RESULTS: During a median follow-up of 10.9 years, a total of 10,841 incident prostate cancer occurred. The hazard ratios (95% confidence intervals) of prostate cancer for each interquartile range increase in PM CONCLUSIONS: Long-term exposure to air pollutants may be positively associated with an elevated risk of prostate cancer, particularly for NO